Hearing loss loci segregating in consanguineous families from India and Pakistan were ascertained. Each family consisted of at least four affected children related to each other through a consanguineous union. Some of these families mapped to known loci such as DFNB3, DFNB4, DFNB6, DFNB8/DFNB10 and DFNB12. Others represent mutations in new DFNB genes that are being mapped such as DFNB18. A large number of additional consanguineous Indian families with nonsyndromic hereditary hearing impairment have recently been ascertained which support LOD scores over 3. DNA samples from these families are being analyzed for localization to known loci. Any families unlinked to the known DFNB and DFNA loci will then be mapped to find additional locations for recessive loci causing nonsyndromic hereditary hearing impairment. - recessive deafness, genetic mapping, cloning, unconventional myosins, MYO15, DFNA and DFNB loci - Human Subjects & Human Subjects: Interview, Questionaires, or Surveys Only